fix(types): use ContextVariableMap in Context<any> (#3134)

* fix(types): use `ContextVariableMap` in `Context<any>`

* use `any`

src/context.ts

@@ -519,9 +519,15 @@ export class Context<
    *   await next()
    * })
    * ```
-```
    */
-  set: Set<E> = (key: unknown, value: unknown) => {
+  set: Set<
+    IsAny<E> extends true
+      ? {
+          // eslint-disable-next-line @typescript-eslint/no-explicit-any
+          Variables: ContextVariableMap & Record<string, any>
+        }
+      : E
+  > = (key: string, value: unknown) => {
     this.#var ??= new Map()
     this.#var.set(key, value)
   }
@@ -539,7 +545,14 @@ export class Context<
    * })
    * ```
    */
-  get: Get<E> = (key: unknown) => {
+  get: Get<
+    IsAny<E> extends true
+      ? {
+          // eslint-disable-next-line @typescript-eslint/no-explicit-any
+          Variables: ContextVariableMap & Record<string, any>
+        }
+      : E
+  > = (key: string) => {
     return this.#var ? this.#var.get(key) : undefined
   }
 

src/types.test.ts

@@ -1,7 +1,7 @@
 /* eslint-disable @typescript-eslint/ban-types */
 /* eslint-disable @typescript-eslint/no-unused-vars */
 import { expectTypeOf } from 'vitest'
-import type { Context } from './context'
+import { Context } from './context'
 import { createMiddleware } from './helper/factory'
 import { Hono } from './hono'
 import { poweredBy } from './middleware/powered-by'
@@ -1748,6 +1748,14 @@ describe('ContextVariableMap type tests', () => {
       return c.json(0)
     })
   })
+
+  it('Should use ContextVariableMap when c is Context<any>', () => {
+    const c = new Context(new Request('http://localhost'))
+    expectTypeOf(c.get('payload')).toEqualTypeOf<string>()
+    expectTypeOf(c.var.payload).toEqualTypeOf<string>()
+    // @ts-expect-error the value of payload should be string
+    expectTypeOf(c.set('payload', 123))
+  })
 })
 
 /**